1. Field of Invention
Embodiments of the invention relate to uninterruptible power supplies. More specifically, at least one embodiment relates to an apparatus, system and method for independently controlling the power outlets of a UPS.
2. Discussion of Related Art
At present, uninterruptible power supplies (“UPS”) sometimes include one or more receptacle outlets that can be isolated by the UPS, for example, to shut down a connected load before the batteries of the UPS are fully discharged. Other UPSs may isolate one or more receptacle outlets when the load supplied from a master outlet which is not switched is reduced below a minimum value. Other UPSs employ a serial communication network to provide a UPS with an indication that loads connected to a plurality of receptacle outlets have been shut down so that the UPS can then shut down itself. However, such an approach treats a plurality of receptacle outlets and the corresponding plurality of electrical loads as a single load. As a result, a configuration of an operational sequence for powering down the load is not customized for the individual electrical loads. Often, the load includes one or more servers that ideally are shut down in a particular fashion to avoid a loss of data and rebooted at the appropriate moment following the restoration of power. Thus, known UPS systems do not adequately provide for an individualized approach for shutting down, isolating and subsequently rebooting the servers.
For example, some prior art UPSs included a plurality of receptacle outlets which supply power to separate electrical loads via separate power circuits where, for example, each receptacle outlet is connected to one of the respective loads. Such a UPS may be included in a system that also includes a communication device. According to one approach, the communication device allows communication from a single serial port to a single device that can communicate with a plurality of electrical loads, for example, computers and/or servers. One or more of the receptacle outlets may be switchable such that power may be turned off to one or more of the loads based on an established set of conditions that may include a condition of the UPS and/or a condition of the load.